Molecular epidemiology and transmission dynamics of multi-drug resistant tuberculosis strains using whole genome sequencing in the Amhara region, Ethiopia.

BACKGROUND: Drug resistant Mycobacterium tuberculosis prevention and care is a major challenge in Ethiopia. The World health organization has designated Ethiopia as one of the 30 high burden multi-drug resistant tuberculosis (MDR-TB) countries. There is limited information regarding genetic diversity and transmission dynamics of MDR-TB in Ethiopia. OBJECTIVE: To investigate the molecular epidemiology and transmission dynamics of MDR-TB strains using whole genome sequence (WGS) in the Amhara region. METHODS: Forty-five MDR-TB clinical isolates from Amhara region were collected between 2016 and 2018, and characterized using WGS and 24-loci Mycobacterium Interspersed Repetitive Units Variable Number of Tandem Repeats (MIRU-VNTR) typing. Clusters were defined based on the maximum distance of 12 single nucleotide polymorphisms (SNPs) or alleles as the upper threshold of genomic relatedness. Five or less SNPs or alleles distance or identical 24-loci VNTR typing is denoted as surrogate marker for recent transmission. RESULTS: Forty-one of the 45 isolates were analyzed by WGS and 44% (18/41) of the isolates were distributed into 4 clusters. Of the 41 MDR-TB isolates, 58.5% were classified as lineage 4, 36.5% lineage 3 and 5% lineage 1. Overall, TUR genotype (54%) was the predominant in MDR-TB strains. 41% (17/41) of the isolates were clustered into four WGS groups and the remaining isolates were unique strains. The predominant cluster (Cluster 1) was composed of nine isolates belonging to lineage 4 and of these, four isolates were in the recent transmission links. CONCLUSIONS: Majority of MDR-TB strain cluster and predominance of TUR lineage in the Amhara region give rise to concerns for possible ongoing transmission. Efforts to strengthen TB laboratory to advance diagnosis, intensified active case finding, and expanded contact tracing activities are needed in order to improve rapid diagnosis and initiate early treatment. This would lead to the interruption of the transmission chain and stop the spread of MDR-TB in the Amhara region.

Molecular mechanisms underlying guanylin-induced transcellular Cl- secretion into the intestinal lumen of seawater-acclimated eels.

Guanylin (GN) stimulates Cl- secretion into the intestinal lumen of seawater-acclimated eels, but the molecular mechanisms of transepithelial Cl- transport are still unknown. In Ussing chamber experiments, we confirmed that mucosal application of eel GN reversed intestinal serosa-negative potential difference, indicating Cl- secretion. Serosal application of DNDS or mucosal application of DPC inhibited the GN effect, but serosal application of bumetanide had no effect. Removal of HCO3- from the serosal fluid also inhibited the GN effect. In intestinal sac experiments, mucosal GN stimulated luminal secretion of both Cl- and Na+, which was blocked by serosal DNDS. These results suggest that Cl- is taken up at the serosal side by DNDS-sensitive anion exchanger (AE) coupled with Na+-HCO3- cotransporter (NBC) but not by Na+-K+-2Cl- cotransporter 1 (NKCC1), and Cl- is secreted by unknown DPC-sensitive Cl- channel (ClC) at the mucosal side. The transcriptomic analysis combined with qPCR showed low expression of NKCC1 gene and no upregulation of the gene after seawater transfer, while high expression of ClC2 gene and upregulation after seawater transfer. In addition, SO42- transporters (apical Slc26a3/6 and basolateral Slc26a1) are also candidates for transcellular Cl- secretion in exchange of luminal SO42. Na+ secretion could occur through a paracellular route, as Na+-leaky claudin15 was highly expressed and upregulated after seawater transfer. High local Na+ concentration in the lateral interspace produced by Na+/K+-ATPase (NKA) coupled with K+ channels (Kir5.1b) seems to facilitate the paracellular transport. In situ hybridization confirmed the expression of the candidate genes in the epithelial enterocytes. Together with our previous results, we suggest that GN stimulates basolateral NBCela/AE2 and apical ClC2 to increase transcellular Cl- secretion in seawater eel intestine, which differs from the involvement of apical CFTR and basolateral NKCC1 as suggested in mammals and other teleosts.

Morphological and functional development of the spiral intestine in cloudy catshark (Scyliorhinus torazame).

Cartilaginous fish have a comparatively short intestine known as the spiral intestine that consists of a helical spiral of intestinal mucosa. However, morphological and functional development of the spiral intestine has not been fully described. Unlike teleosts, cartilaginous fish are characterized by an extremely long developmental period in ovo or in utero; for example, in the oviparous cloudy catshark (Scyliorhinus torazame), the developing fish remains inside the egg capsule for up to 6 months, suggesting that the embryonic intestine may become functional prior to hatching. In the present study, we describe the morphological and functional development of the spiral intestine in the developing catshark embryo. Spiral formation of embryonic intestine was completed at the middle of stage 31, prior to 'pre-hatching', which is a developmental event characterized by the opening of the egg case at the end of the first third of development. Within 48 h of the pre-hatching event, egg yolk began to flow from the external yolk sac into the embryonic intestine via the yolk stalk. At the same time, there was a rapid increase in mRNA expression of the peptide transporter pept1 and neutral amino acid transporter slc6a19 Secondary folds in the intestinal mucosa and microvilli on the apical membrane appeared after pre-hatching, further supporting the onset of nutrient absorption in the developing intestine at this time. We demonstrate the acquisition of intestinal nutrient absorption at the pre-hatching stage of an oviparous elasmobranch.

Identification of four patients with colistin-resistant Escherichia coli containing the mobile colistin resistance mcr-1 gene from a single health system in Michigan.

Clinical Enterobacteriacae isolates with a colistin minimum inhibitory concentration (MIC) ≥4 mg/L from a United States hospital were screened for the mcr-1 gene using real-time polymerase chain reaction (RT-PCR) and confirmed by whole-genome sequencing. Four colistin-resistant Escherichia coli isolates contained mcr-1. Two isolates belonged to the same sequence type (ST-632). All subjects had prior international travel and antimicrobial exposure.

Molecular mechanisms for intestinal HCO3- secretion and its regulation by guanylin in seawater-acclimated eels.

The intestine of marine teleosts secretes HCO3- into the lumen and precipitates Ca2+ and Mg2+ in the imbibed seawater as carbonates to decrease luminal fluid osmolality and facilitate water absorption. However, the hormonal regulation of HCO3- secretion is largely unknown. Here, mucosally added guanylin (GN) increased HCO3- secretion, measured by pH-stat, across isolated seawater-acclimated eel intestine bathed in saline at pH 7.4 (5% CO2). The effect of GN on HCO3- secretion was slower than that on the short-circuit current, and the time course of the GN effect was similar to that of bumetanide. Mucosal bumetanide and serosal 4,4'-dinitrostilbene-2,2'-disulfonic acid (DNDS) inhibited the GN effect, suggesting an involvement of apical Na+-K+-2Cl- cotransporter (NKCC2) and basolateral Cl-/HCO3- exchanger (AE)/Na+-HCO3- cotransporter (NBC) in the GN effect. As mucosal DNDS failed to inhibit the GN effect, apical DNDS-sensitive AE may not be involved. To identify molecular species of transporters involved in the GN effect, we performed RNA-seq analyses followed by quantitative real-time PCR after transfer of eels to seawater. Among the genes upregulated after seawater transfer, AE genes (draa, b, and pat1a, c) on the apical membrane, and NBC genes (nbce1a, n1, n2a) and an AE gene (sat-1) on the basolateral membrane were candidates involved in HCO3- secretion. Judging from the slow effect of GN, we suggest that GN inhibits NKCC2b on the apical membrane and decreases cytosolic Cl- and Na+, which then activates apical DNDS-insensitive DRAs and basolateral DNDS-sensitive NBCs to enhance transcellular HCO3- flux across the intestinal epithelia of seawater-acclimated eels.

Preparatory Mechanisms for Salinity Tolerance in Two Congeneric Anuran Species Inhabiting Distinct Osmotic Habitats.

Anurans occupy a wide variety of habitats of diverse salinities, and their osmoregulatory ability is strongly regulated by hormones. In this study, we compared the adaptability and hormonal responses to osmotic stress between two kajika frogs, Buergeria japonica (B.j.) and B. buergeri, (B.b.), which inhabit coastal brackish waters (BW) in the Ryukyu Islands and freshwater (FW) in the Honshu, respectively. Both hematocrit and plasma Na+ concentration were significantly higher in B.j. than in B.b. when both were kept in FW. After transfer to one-third seawater (simulating the natural BW environment), which is slightly hypertonic to their body fluids, their body mass decreased and plasma Na concentration increased significantly in both species. After transfer, plasma Na+ concentration increased significantly in both species. We examined the gene expression of two major osmoregulatory hormones, arginine vasotocin (AVT) and atrial natriuretic peptide (ANP), after partial cloning of their cDNAs. ANP mRNA levels were more than 10-fold higher in B.j. than in B.b. in FW, but no significant difference was observed for AVT mRNA levels due to high variability, although the mean value of B.j. was twice that of B.b. Both AVT and ANP mRNA levels increased significantly after transfer to BW in B.b. but not in B.j., probably because of the high levels in FW. These results suggest that B.j. maintains high plasma Na+ concentration and anp gene expression to prepare for the future encounter of the high salinity. The unique preparatory mechanism may allow B.j. wide distribution in oceanic islands.

Health literacy and surgery expectations in total hip and knee arthroplasty patients.

OBJECTIVES: This study assessed patients' health literacy and expectations for total hip (THA) and total knee (TKA) replacement surgery, and compared health literacy levels of patients and their caregivers. METHODS: A convenience sample of 200 THA/TKA participants, patients and their caregivers, participated in this study. RESULTS: Results demonstrated no statistical difference in health literacy between patients and their caregivers. However, patients with lower health literacy had significantly lower expectations for walking after surgery. CONCLUSIONS: Practices should be aware that caregivers may not be any better equipped to consume and use complicated patient education materials than the patient they are assisting. Additionally, lower health literacy, rather than or in addition to race or social factors, may contribute to disparities in opting for THA/TKA because of lower expectations for walking after surgery. PRACTICE IMPLICATIONS: Healthcare practices should develop patient educational materials that are easy for all patients and caregivers to understand, especially those with low health literacy. Additional patient education and counseling may help patients with low health literacy realistically align their expectations and mitigate barriers to consenting to surgery due to low expectations.

Molecular and evolutionary perspectives of the renin-angiotensin system from lamprey.

The recent advance and revision on the renin-angiotensin system in lamprey were summarized and we emphasized that presence of two types of angiotensins (Angs) in lamprey. Due to the parasitic nature on fish blood, teleost-type Angs were produced in their buccal gland and secreted into the lamphredin to evade the host immunorejection. A native lamprey angiotensinogen (AGT) was identified in genome and it retains serine-protease inhibitor activity for thrombin that regulates the blood coagulation pathway. The native lamprey angiotensin II (Lp-Ang II) is hypotensive instead of hypertensive, suggesting a functional divergence on cardiovascular regulation from the main vertebrate groups. The renin gene was absent from the lamprey genome so far, and the mutation on the renin-recognition site on lamprey AGT suggested that other proteases may have replaced the role of renin. Lp-Ang II was shown to bind to AT1 receptor and internalized, but the downstream signaling was still unknown. Molecular and phylogenetic evidence on invertebrate ACE-like proteins indicated that they were not homologous to those in vertebrates and could be acting on other native peptides. Although it was generally believed that the RAS was a well-conserved hormone system in vertebrates and invertebrates, revision by molecular data indicated that invertebrates lack homologous RAS components while lamprey possess an almost complete RAS. This suggests that the hormone cascade system was first evolved around cyclostome emergence and invertebrates could have taken up the RAS components from vertebrates through horizontal gene transfer.

Changes in Plasma and Tissue Long-Chain Polyunsaturated Fatty Acid (LC-PUFA) Content in the Eel Anguilla japonica After External and Internal Osmotic Stress.

We investigated the effect of external and internal osmotic stress on the profile of long-chain polyunsaturated fatty acids (LC-PUFA) in euryhaline eels Anguilla japonica. Freshwater (FW) fish were transferred to seawater (SW) for external osmotic stress or subjected to internal stress through injection with hypertonic saline. FW eels injected with isotonic saline served as controls. Plasma osmolality, Na+ concentration, and gill Na+/K+ -ATPase activity increased, but hematocrit decreased compared with controls in eels exposed to external or internal osmotic stress. The expression of two major transporter genes for SW adaptation, the Na+ -K+ -2Cl - co-transporter 1a (NKCC1a) in the gill and NKCC2b in the intestine, was up-regulated only in SW-transferred eels, suggesting a direct impact of SW on the gill and intestine via SW ingestion. Total LC-PUFA contents and DHA (22:6 n-3) increased in the gill and liver of SW-transferred eels and in the intestine of hypertonic saline-injected eels. However, total LC-PUFA content in plasma decreased after both external and internal osmotic stimuli. In contrast, the gene expression of two key enzymes involved in the LC-PUFA biosynthesis, Δ6 fatty acid desaturase and elongase, did not change in the gill, intestine and liver of osmotically stressed eels. These results indicate that LC-PUFA is possibly involved in osmoregulation and the increased LC-PUFA contents of osmoregulatory organs might be a result of LC-PUFA transport via circulation, rather than through de novo biosynthesis.

Safety and Accuracy of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Highly Pathogenic Organisms.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) sample preparation methods, including the direct, on-plate formic acid, and ethanol/formic acid tube extraction methods, were evaluated for their ability to render highly pathogenic organisms nonviable and safe for handling in a biosafety level 2 laboratory. Of these, the tube extraction procedure was the most successful, with none of the tested strains surviving this sample preparation method. Tube extracts from several agents of bioterrorism and their near neighbors were analyzed in an eight-laboratory study to examine the utility of the Bruker Biotyper and Vitek MS MALDI-TOF MS systems and their in vitro diagnostic (IVD), research-use-only, and Security-Relevant databases, as applicable, to accurately identify these agents. Forty-six distinct strains of Bacillus anthracis, Yersinia pestis, Francisella tularensis, Burkholderia mallei, Burkholderia pseudomallei, Clostridium botulinum, Brucella melitensis, Brucella abortus, Brucella suis, and Brucella canis were extracted and distributed to participating laboratories for analysis. A total of 35 near-neighbor isolates were also analyzed.

Molecular mechanisms underlying active desalination and low water permeability in the esophagus of eels acclimated to seawater.

Marine teleosts can absorb imbibed seawater (SW) to maintain water balance, with esophageal desalination playing an essential role. NaCl absorption from luminal SW was enhanced 10-fold in the esophagus of SW-acclimated eels, and removal of Na+ or Cl- from luminal SW abolished the facilitated absorption, indicating coupled transport. Mucosal/serosal application of various blockers for Na+/Cl- transporters profoundly decreased the absorption. Among the transporter genes expressed in eel esophagus detected by RNA-seq, dimethyl amiloride-sensitive Na+/H+ exchanger (NHE3) and 4,4'-diisothiocyano-2,2'-disulfonic acid-sensitive Cl-/[Formula: see text] exchanger (AE) coupled by the scaffolding protein on the apical membrane of epithelial cells, and ouabain-sensitive Na+-K+-ATPases (NKA1α1c and NKA3α) and diphenylamine-2-carboxylic acid-sensitive Cl- channel (CLCN2) on the basolateral membrane, may be responsible for enhanced transcellular NaCl transport because of their profound upregulation after SW acclimation. Upregulated carbonic anhydrase 2a (CA2a) supplies H+ and [Formula: see text] for activation of the coupled NHE and AE. Apical hydrochlorothiazide-sensitive Na+-Cl- cotransporters and basolateral Na+-[Formula: see text] cotransporter (NBCe1) and AE1 are other possible candidates. Concerning the low water permeability that is typically seen in marine teleost esophagus, downregulated aquaporin genes (aqp1a and aqp3) and upregulated claudin gene (cldn15a) are candidates for transcellular/paracellular route. In situ hybridization showed that these upregulated transporters and tight-junction protein genes were expressed in the absorptive columnar epithelial cells of eel esophagus. These results allow us to provide a full picture of the molecular mechanism of active desalination and low water permeability that are characteristic to marine teleost esophagus and gain deeper insights into the role of gastrointestinal tracts in SW acclimation.

Development of an animal-borne blood sample collection device and its deployment for the determination of cardiovascular and stress hormones in phocid seals.

An animal-borne blood sampler with data-logging functions was developed for phocid seals, which collected two blood samples for the comparison of endocrinological/biochemical parameters under two different conditions. The sampler can be triggered by preset hydrostatic pressure, acceleration (descending or ascending), temperature, and time, and also manually by light. The sampling was reliable with 39/50 (78%) successful attempts to collect blood samples. Contamination of fluids in the tubing to the next blood sample was <1%, following the prior clearance of the tubing to a waste syringe. In captive harbor seals (Phoca vitulina), the automated blood-sampling method was less stressful than direct blood withdrawal, as evidenced by lower levels of stress hormones (P < 0.05 for ACTH and P = 0.078 for cortisol). HPLC analyses showed that both cortisol and cortisone were circulating in seal blood. Using the sampler, plasma levels of cardiovascular hormones, atrial natriuretic peptide (ANP), AVP, and ANG II were compared in grey seals (Halichoerus grypus), between samples collected when the animals were on land and in the water. HPLC analyses determined that [Met12] ANP (1-28) and various forms of angiotensins (ANG II, III, and IV) were circulating in seal blood. Although water immersion profoundly changes the plasma levels of cardiovascular hormones in terrestrial mammals, there were only tendencies toward an increase in ANP (P = 0.069) and a decrease in AVP (P = 0.074) in the seals. These results suggest that cardiovascular regulation in phocid seals may have undergone adaptation during evolution of the carnivore to a semiaquatic lifestyle.

Rapid surveillance for health events following a mass meningococcal B vaccine program in a university setting: A Canadian Immunization Research Network study.

An outbreak of Neisseria meningitidis serotype B infection occurred at a small residential university; public health announced an organizational vaccination program with the 4-component Meningococcal B (4CMenB) vaccine (Bexsero(TM), Novartis/GlaxoSmithKline Inc.) several days later. Since there were limited published data on reactogenicity of 4CMenB in persons over 17years of age, this study sought to conduct rapid surveillance of health events in vaccinees and controls using an online survey. Vaccine uptake was 84.7% for dose 1 (2967/3500) and 70% (2456/3500) for dose 2; the survey response rates were 33.0% (987/2967) and 18.7% (459/2456) in dose 1 and dose 1 recipients respectively, and 12% in unvaccinated individuals (63/533). Most students were 20-29years of age (vaccinees, 64.0%; controls, 74.0). A new health problem or worsening of an existing health problem was reported by 30.0% and 30.3% of vaccine recipients after doses 1 and 2 respectively; and by 15.9% of controls. These health problems interfered with the ability to perform normal activities in most vaccinees reporting these events (74.7% post dose 1; 62.6% post dose 2), and in 60% of controls. The health problems led to a health care provider visit (including emergency room) in 12.8% and 14.4% of vaccinees post doses 1 and 2, respectively and in 40% of controls. The most common reactions in vaccinees were injection site reactions (20.6% post dose 1, 16.1% post dose 20 and non-specific systemic complaints (22.6% post dose 1, 17.6% post dose 2). No hospitalizations were reported. An online surveillance program during an emergency meningococcal B vaccine program was successfully implemented, and detected higher rates of health events in vaccinees compared to controls, and high rates of both vaccinees and controls seeking medical attention. The types of adverse events reported by young adult vaccinees were consistent with those previously.

High-throughput vector-borne disease environmental surveillance by polymerase chain reaction according to international accreditation requirements.

Although vector-borne diseases are specific to the region of the host, there is a necessity for surveillance or reference laboratories to perform standardized, high-throughput testing capable of meeting the needs of a changing military environment and response efforts. The development of standardized, high-throughput, semiquantitative real-time and reverse transcription real-time polymerase chain reaction (PCR) methods allows for the timely dissemination of data to interested parties while providing a platform in which long-term sample storage is possible for the testing of new pathogens of interest using a historical perspective. PCR testing allows for the analysis of multiple pathogens from the same sample, thus reducing the workload of entomologists in the field and increasing the ability to determine if a pathogen has spread beyond traditionally defined locations. US Army Public Health Command Region-Europe (USAPHCR-Europe) Laboratory Sciences (LS) has standardized tests for 9 pathogens at multiple life stages. All tests are currently under international accreditation standards. Using these PCR methods and laboratory model, which have universal Department of Defense application, the USAPHCR-Europe LS will generate quality data that is scientifically sound and legally defensible to support force health protection for the US military in both deployed and garrison environments.

Mechanisms of guanylin action on water and ion absorption at different regions of seawater eel intestine.

Guanylin (GN) inhibited water absorption and short-circuit current (Isc) in seawater eel intestine. Similar inhibition was observed after bumetanide, and the effect of bumetanide was abolished by GN or vice versa, suggesting that both act on the same target, Na(+)-K(+)-2Cl(-) cotransporter (NKCC), which is a key player for the Na(+)-K(+)-Cl(-) transport system responsible for water absorption in marine teleost intestine. However, effect of GN was always greater than that of bumetanide: 10% greater in middle intestine (MI) and 40% in posterior intestine (PI) for Isc, and 25% greater in MI and 34% in PI for water absorption. After treatment with GN, Isc decreased to zero, but 20-30% water absorption still remained. The remainder may be due to the Cl(-)/HCO3 (-) exchanger and Na(+)-Cl(-) cotransporter (NCC), since inhibitors for these transporters almost nullified the remaining water absorption. Quantitative PCR analysis revealed the presence of major proteins involved in water absorption; the NKCC2ß and AQP1 genes whose expression was markedly upregulated after seawater acclimation. The SLC26A6 (anion exchanger) and NCCß genes were also expressed in small amounts. Consistent with the inhibitors' effect, expression of NKCC2ß was MI > PI, and that of NCCß was MI << PI. The present study showed that GN not only inhibits the bumetanide-sensitive Na(+)-K(+)-Cl(-) transport system governed by NKCC2ß, but also regulates unknown ion transporters different from GN-insensitive SLC26A6 and NCC. A candidate is cystic fibrosis transmembrane conductance regulator Cl(-) channel, as demonstrated in mammals, but its expression is low in eel intestine, and its role may be minor, as indicated by the small effect of its inhibitors.

Direct observation of dynamic charge stripes in La2-xSrxNiO4.

The insulator-to-metal transition continues to be a challenging subject, especially when electronic correlations are strong. In layered compounds, such as La2-xSrxNiO4 and La2-xBaxCuO4, the doped charge carriers can segregate into periodically spaced charge stripes separating narrow domains of antiferromagnetic order. Although there have been theoretical proposals of dynamically fluctuating stripes, direct spectroscopic evidence of charge-stripe fluctuations has been lacking. Here we report the detection of critical lattice fluctuations, driven by charge-stripe correlations, in La2-xSrxNiO4 using inelastic neutron scattering. This scattering is detected at large momentum transfers where the magnetic form factor suppresses the spin fluctuation signal. The lattice fluctuations associated with the dynamic charge stripes are narrow in q and broad in energy. They are strongest near the charge-stripe melting temperature. Our results open the way towards the quantitative theory of dynamic stripes and for directly detecting dynamical charge stripes in other strongly correlated systems, including high-temperature superconductors such as La2-xSrxCuO4.

Changes in plasma angiotensin II, aldosterone, arginine vasotocin, corticosterone, and electrolyte concentrations during acclimation to dry condition and seawater in the crab-eating frog.

The crab-eating frog Fejervarya cancrivora inhabits mangrove swamps and marshes in Southeast Asia. In the present study, circulating angiotensin II (Ang II), aldosterone (Aldo), arginine vasotocin (AVT), and corticosterone (Cort) concentrations as well as various blood parameters were studied under osmotically stressful conditions. Following acclimation to hyperosmotic seawater and dry condition for 5days, body weight was significantly decreased. Under both conditions, plasma Na(+), Cl(-), and urea concentrations, hematocrit values (Ht; blood volume indicator), and osmolality were significantly increased. Dehydration associated with hypovolemic and hyperosmotic states of body fluids was induced during acclimation to hyperosmotic seawater and dry condition in the crab-eating frogs. Ang II, Aldo, AVT, and Cort were maintained within relatively narrow concentration ranges in the control frogs; however, in frogs under dry and hyperosmotic seawater conditions, large variations were observed among individuals in each group. Mean plasma Ang II and Aldo concentrations significantly increased in hyperosmotic seawater-acclimated and desiccated frogs. Although mean plasma AVT concentrations in dehydrated frogs of both the groups were approximately 2.0-3.5 times higher than those in the control frogs, the differences were not significant because of the variation. There was a significant correlation between plasma osmolality and AVT as well as Ang II but not Aldo. A significant correlation was also observed between Ht and AVT as well as Ang II. Plasma Ang II was significantly correlated with plasma Aldo. These results indicate that the crab-eating frogs may exhibit similar physiological responses to both seawater-acclimated and dry conditions. It appears that under dehydrated conditions, osmoregulatory mechanisms participate in stabilization of the situation. The renin-angiotensin system may have pivotal roles in body fluid regulation under volemic and osmotic stress in the Fejervarya species with unique osmoregulation.

Magnonlike dispersion of spin resonance in Ni-doped BaFe2As2.

Inelastic neutron scattering measurements on Ba(Fe0.963Ni0.037)2As2 manifest a neutron spin resonance in the superconducting state with anisotropic dispersion within the Fe layer. Whereas the resonance is sharply peaked at the antiferromagnetic (AFM) wave vector Q(AFM) along the orthorhombic a axis, the resonance disperses upwards away from Q(AFM) along the b axis. In contrast to the downward dispersing resonance and hourglass shape of the spin excitations in superconducting cuprates, the resonance in electron-doped BaFe2As2 compounds possesses a magnonlike upwards dispersion.

Effect of electron correlations on magnetic excitations in the isovalently doped iron-based superconductor Ba(Fe(1-x)Ru(x))(2)As(2).

Magnetic correlations in isovalently doped Ba(Fe(1-x)Ru(x))(2)As(2) (x = 0.25, T(c) = 14.5 K; x = 0.35, T(c) = 20 K) are studied by elastic and inelastic neutron scattering techniques. A relatively large superconducting spin gap accompanied by a weak resonance mode is observed in the superconducting state in both samples. In the normal state, the magnetic excitation intensity is dramatically reduced with increasing Ru doping toward the optimally doped regime. Our results favor that the weakening of the electron-electron correlations by Ru doping is responsible for the dampening of the resonance mode, as well as the suppression of the normal state antiferromagnetic correlations near the optimally doped regime in this system.